Reciprocating-pump valves actuated by pressure-gradient reversals within the fluid passing through their sealing surfaces are generally spring-loaded, and, or gravity assisted in one manner or another. Such valves require additional hydraulic energy to overcome the spring-loading or dead weight of the valve, which interferes with the cyclic harmony and smooth rhythmic operation of the pressure-actuated valve, thus reducing the efficiency of pumps employing such valves. Therefore, if a pressure-actuated reciprocating pump valve were designed that was neither spring-loaded nor gravity-assisted in its operation, such as a valve that was neutrally-buoyant, or of the same overall density as that of the fluid being conveyed through it, such a valve would react immediately to pressure-gradient reversals, conserve hydraulic energy, and increase pump efficiency.
Reciprocating piston pumps and reciprocating plunger pumps used in oil-field operations to pump sand-laden drilling fluids or hydraulic-fracture fluids, and reciprocating pumps used by the mining industry to pump abrasive sluries through pipelines employ valves which are guided by means of valve stems and valve guides with cross arms. Such valve guides and cross arms, which are an integral part of the valve seat, are relatively massive valve-seat elements, and are located immediately upstream from the valve in the region where the fluid is pumped through the valve seat, thus, creating a sizeable obstruction right in the region where the concentrated and abrasive fluid funnels through the valve seat. Such an opstruction interferes with the flow of fluid through the valve-seat orifice and the smooth rhythmic operation of the valve, resulting in wasted hydraulic energy and reduced pump efficiency. Therefore, if a reciprocating-pump valve were designed that eliminated such large mid-stream opstructions in the critical valve-seat region, and, instead, guided the valve externally into the valve seat by means of radial guide fins which offered only minimal resistance to the abrasive fluid pumped through the valve, then such a valve system would further conserve hydraulic energy and should further improve pump efficiency.
Pump valves and valve seats used in reciprocating pumps are often so badly eroded by abrasive fluids passing through the valve seats and around the valves that pumping efficiency is reduced considerably. Therefore, if the valve seat and the sealing surface of the valve were protected by deflecting surfaces in such a manner so as to reduce such abrasion or erosion then such a valve system would also conserve hydraulic energy and should also improve pump efficiency.